A cellular confinement structure serves to increase the load bearing capacity, stability, and erosion resistance of infill materials which are placed within the cells of the system and can serve to protect underlying soils or as a protective layer over pond liners or other protective membranes. A commercially available system is Geoweb® plastic web confinement structure sold by Reynolds Presto Products Inc., Appleton, Wis. Geoweb® cells are made from high density polyethylene strips that are joined by welds on their faces in a side-by-side relationship at alternating spaces so that when the strips are stretched out in a direction perpendicular to the faces of the strips, the resulting section is honeycomb-like in appearance, with sinusoidal or undulated-shaped cells. Geoweb® sections are lightweight and are shipped in their collapsed form for ease in handling and installation. Geoweb® systems have been described in U.S. Pat. Nos. 8,092,122; 6,395,372; 5,927,906; 5,449,543; 4,778,309; and 4,965,097, each of these patents being incorporated by reference herein.
A challenge for channels and slopes includes the limitations of length of cellular confinement sections used upon slopes due to the cumulative forces of the weight of the infill contained by the cellular confinement section upon the welds that define the shape of expanded cell. Either stakes, or tendons, or both needs to be used to transfer the forces from the filled cell to the ground, and this transfer of force needs to occur in sufficient locations to allow for the forces never to exceed the capacity of the welds. Another challenge associated with the use of cellular confinement systems is that the fill material and the cellular confinement sections may be displaced during installation and long-term operation. Erosion below the cellular confinement section may cause infill to drop out of the cells. Applied forces such as hydraulic uplift or ice action may lift the cellular confinement section or lift the fill material out of the cells. Translational movement of the cellular confinement section may also occur in channel lining applications, or when installing on steep slopes.
In one improvement, a load transfer device was developed and sold by Reynolds Presto Products under the tradename Atra® Clip. This load transfer device is described in U.S. Pat. No. 5,927,906, incorporated herein by reference, and depicted in FIGS. 21 and 22. Continuing improvements in these types of systems and connections are desirable.